Dizziness in the third trimester

As pregnancy advances, lying flat or standing suddenly can affect blood flow and make you lightheaded. Heat, dehydration, going too long without food, or low iron can also contribute. Feeling that the room is spinning points toward a balance problem rather than simple lightheadedness.

Dizziness is a symptom, not a diagnosis. A clinician may check your blood pressure, pulse, hydration, blood count and blood sugar, while considering symptoms such as palpitations or anxiety. Possible related conditions include [Anaemia](/conditions/anaemia/), [Dehydration](/conditions/dehydration/) and [Iron Deficiency Anaemia](/conditions/iron-deficiency-anaemia/).

Sit or lie on your side in a cool place, loosen tight clothing and ask someone to stay with you if you feel faint. Rise slowly, drink fluids, and eat a snack if you have missed a meal and can safely eat. Avoid driving, climbing or bathing alone until the feeling has passed.

Mention repeated episodes to your midwife, obstetric team or GP. Do not start iron, glucose products or other treatment without advice. Heat exposure and fluid loss may contribute to [Heat Exhaustion](/conditions/heat-exhaustion/), while low blood sugar is discussed under [Hypoglycaemia](/conditions/hypoglycaemia/).

Seek urgent maternity or emergency help for fainting, chest pain, trouble breathing, severe headache, vision changes, new weakness, confusion, heavy bleeding, severe abdominal pain, regular painful contractions, reduced fetal movement or dizziness that does not settle. Arrange prompt assessment for recurrent dizziness, racing or irregular heartbeat, or symptoms that follow heat or poor intake. Other causes can include [Atrial Fibrillation](/conditions/atrial-fibrillation/), [Benign Paroxysmal Positional Vertigo](/conditions/benign-paroxysmal-positional-vertigo/) or [Generalised Anxiety Disorder](/conditions/generalised-anxiety-disorder/).

Ask whether your blood pressure, blood count, iron level, hydration and glucose need checking. Explain when episodes happen, how long they last, whether you feel spinning or faint, and whether palpitations, headache or vision changes occur.